Patent References 3637308 3790267 Exposure method and apparatus Method and apparatus for distortion correction in optical projectors Optical apparatus in which image distortion is removed Method and system for compensating for image distortion caused by off-axis image projection Fiberoptic face plate stop for digital micromirror device projection system Inclination angle sensing apparatus for use in a projector Method and apparatus for pre-compensating an asymmetrical picture in a projection system for displaying a picture Imaging optical system InventorsAssigneeApplicationNo. 446796 filed on 12/24/1999US Classes:353/69, DISTORTION COMPENSATION348/744, Projection device348/745, With alignment, registration or focus348/747, Raster size or position compensation353/70For projection axis inclined to screenExaminersPrimary: Adams, Russell E.Assistant: Fuller, Rodney Attorney, Agent or FirmInternational ClassesG03B 021/00H04N 005/64 H04N 003/22 H04N 003/223 AbstractA method and apparatus for preventing keystone distortion. A projected image is produced by projecting light through a display image rendered on a display device (e.g., and LCD panel) and onto a viewing surface at a non-perpendicular vertical and/or horizontal angle. An original image is deformed in proportion to the angle(s) to produce the display image. The original image may also be resized for storage in memory and/or to fit within a specified or usable area of the display device. An apparatus for preventing keystone distortion includes a digitizer module to receive and resize an original image (e.g., reduce it) for storage and a generator module to resize (e.g., enlarge) the image to fit the display device. Deformation of the image to prevent keystone distortion may be performed in either or both of the digitizer and generator for either or both a vertical and horizontal angle. | |